Abstract

Description

The solar market showed global potential of renewable energy industry by
achieving an explosive growth of 75% annually from 2006 to 2010 with the
support of government's subsidy. However the rapid growth in the short term
had a side effect of increasing the burden of government's subsidy. As the
countries in Europe which are the main demand markets for photovoltaic are
significantly reducing the fund and carrying out the Rooftop policy the demand
for low cost high efficiency solar cell that can generate high output from
small area is growing.

There are many ways to increase the solar cell conversion efficiency but
quantum dot solar cell is especially receiving more attention since it is a
concept that overcomes the theoretical limitations of original solar cell.
Quantum dot is a nano-crystalline structure of several nm to 10 nm surrounded
by high barrier materials and since the electrons and holes inside the quantum
dot are confined in narrow space the energy level becomes discrete. According
to some study research solar cell efficiency can increase up to more than 60%
in theory if the quantum dot characteristics are optimized and utilized.

Quantum dot solar cell can be divided into compound solar cell, silicon solar
cell and nano particle/core shell solar cell depending on the field applied.
Compound solar cell can be applied to satellite, military and concentrated
solar cell and is expected to be commercialized before or after 2020 when
stabilized efficiency of 20% in flat structure and 40% in tandem structure
will be realized. Silicon quantum dot solar cell is expected to replace a-Si
thin film solar cell by 2015 when 20% of stabilized efficiency of tandem
structure is expected to be realized. Technology development is required for
silicon quantum dot solar cell to transfer in to crystalline structure. Nano
particle/core shell solar cell can be applied to DSSC and OPV and is currently
expected to be commercialized in about 2020 when stabilized efficiency of
8%~12% will be reached.

In today's solar cell market where growth in demand of high efficiency solar
is inevitable the importance of Quantum Dot solar cell will be increased and
active research will be expected in each sector as the quantum dot solar cell
development is a promising next generation technology.